Orbital-free ab initio molecular dynamics study of the free liquid surface of Cd.

We report results of an orbital-free \textit{ab initio} molecular dynamics (OF-AIMD) study of the free liquid surface of Cd at 800 K. A key ingredient in the OF-AIMD method is the local ionic pseudopotential describing the ions-valence electrons interaction. We have developed a force-matching method [1] to derive a local ionic pseudopotential suitable to account for a rapidly varying density system, such as a free liquid surface. Results are reported for several structural properties. The calculated reflectivity shows a marked maximum whose origin is related to the surface layering, along with a shoulder located at a much smaller wavevector transfer. \smallskip [1] B. G. del Rio and L. E. Gonzalez, J. Phys.: Condens. Matter \textbf{26}, 465102 (2014)